Yes, OpenWFD was succeeded by MiracleCast http://www.freedesktop.org/wiki/Software/miracle/ from the same developer. I only remembered the OpenWFD presentation at FOSDEM.

MiracleCast requires wpa_supplicant which seems to be available or can be compiled from the sources for the N9. For other prerequisites I have no idea but DBus should be fine though.

Having a working Wifi-Direct functionality would be already quite useful as someone e.g. could implement direct file transfer via Wifi-P2P between N9 and Android smartphones.

Btw, for Miracast screen sharing is there HDMI resolution required? N9 has only FWVGA.

Personally I don't feel an urgent need for Miracast as DNLA/UPnP works fine and there is legacy Video out available although mirroring the display onto a desktop screen would be nice.